Dr Hilary Jones has shared how his 17-year age gap with his wife Dee Thrasher helps keep him "grounded and fit".

The 70-year-old television doctor detailed how he and Thrasher make their relationship work despite their age difference during a recent appearance on the How to be 60 with Kaye Adams podcast.

Asked how he "keeps up" with 53-year-old Thrasher’s active lifestyle, Dr Jones said he does not "feel any pressure at all" to do so and that the couple enjoy exercising together.

"I really enjoy the things we do together, so we'll go walking on the hill. We're always walking and keeping busy," he said. "It’s not a competitive thing at all. We do different types of exercise. I do gym, I still play a little bit of squash, and I do the heavy lifting in the garden, and she does the lighter stuff."

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Dubbing Thrasher a "pilates queen", Dr Jones added: "She's 17 years younger than me and that's exactly how it should be… She's pretty complimentary to me, I hope she means it. She always says, 'I never consider you 70' and I don't behave like I'm 70. I'm still a bit of a child inside."

While Dr Jones' age-gap relationship is going swimmingly, others have succumbed to the challenges that come with it.

In April, Madonna, 63, split from her boyfriend Ahlamalik Williams, 28, after nearly four years together. It was reported that the break-up occurred as it was "hard to keep the relationship alight", but the pair remained "on good terms".

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Age-gap relationships: the pros and cons

Lisa Spitz, counsellor and psychotherapist, tells Yahoo Life UK that there are both benefits and disadvantages to relationships with a large age gap.

While she says generally "too much difference isn't great" she also believes there is "opportunity" within an age-gap in a relationship.

"There's something very beneficial about mixing people in different age groups as you get the opportunity to see the world in a different way, with the wealth of experience meeting naivety and joyfulness."

However, she explains that sometimes there can be a "mismatch of different life experiences".

"The older partner may be looking for someone to ‘mould’ and this could prove problematic as the younger partner matures and potentially wants different things," she adds.

She also highlights the potential for problems with partners being at different life stages.

"The younger partner may want children and the older of the two already has family or doesn’t want any kids," she adds. "There could also be a pressure to perform sexually when the woman is menopausal or the man has prostate issues."

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People in age-gap relationships also often have to face more external judgement than other relationships.

"We get really hung up about age because we have in our head what is socially acceptable in our culture," says Spitz.

"I think there is the classic thought process that a much younger man/woman who is with an older man/woman is a gold digger, we wonder what they have in common and how long it could last."

There are also very different attitudes towards older women dating younger men and younger men dating older women.

"No one questions the sanity of Richard Gere with his much younger partner or Simon Cowell or Rod Stewart but Katie Price or even Joan Collins are often seen as cougars," Spitz says.

"I think attitudes are changing towards women with younger partners and there have been some very successful younger men/older women relationships – Joan Collins and Percy Gibson; Brigitte and Emmanuel Macron to name two but the fact that people still feel the need to comment shows we have a long way to go."

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Age-gap relationships being successful can also depend on whether friends and family show support or not with Spritz urging kindness if a friend or loved-one starts a relationship with a large difference.

"Keep your judgement to yourself and understand your feelings around it," she says.

She also suggests taking time to get to know the new partner so you can make a true assessment of the person.

And if things don't work out she advises being there to pick up the pieces.

So, is age really just a number?

"I think if you find someone you love and want to build a future with, have common values, expectations and great communication they have a good chance of working," Spitz concludes.